The present invention relates to an X or gamma-radiation detector particularly for radiology. It finds applications not only as a low-absorption measuring chamber but also as a high-efficiency radiation detector.
In the prior art X or gamma photon detectors are known which comprise a scintillator element mounted on a photodetector cell. The scintillator element absorbs a part of the X or gamma photons and transforms them into light photons a part of which is absorbed by a photodetector cell. This latter then supplies an electric signal related to the intensity of the incident X or gamma photon beam with a very short response time of the order of a nanosecond.
The present invention provides a special detector arrangement which improves the efficiency very much and so the response time which drops to the level of a picosecond.
In order to improve the efficiency Published German application DE OS 26 22 655 proposes a series arrangement of scintillators and photodetectors. The sensitivity remains low for a large number of elements. Their thickness makes them unsuitable for use as a measuring chamber between a body to be examined and a radiographic film for example. The film in fact retains a trace of the detector.